/* 全局样式 */
:root {
    --primary-color: #4a90e2;
    --secondary-color: #f5f5f5;
    --text-color: #333;
    --card-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
}

body {
    margin: 0;
    padding: 0;
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
    line-height: 1.6;
    color: var(--text-color);
}

/* 导航栏 */
.top-nav {
    background-color: white;
    padding: 1rem;
    box-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
    position: sticky;
    top: 0;
    z-index: 100;
}

.nav-links {
    display: flex;
    justify-content: center;
    gap: 2rem;
}

.nav-links a {
    color: var(--text-color);
    text-decoration: none;
    font-weight: 500;
    transition: color 0.3s ease;
}

.nav-links a:hover {
    color: var(--primary-color);
}

/* logo样式 */
.hero {
    display: flex;
    justify-content: center;
    align-items: center;
    padding: 1rem;
}

.logo-container {
    width: 60px;
    height: 60px;
    display: flex;
    justify-content: center;
    align-items: center;
}

.logo {
    max-width: 100%;
    height: auto;
    border-radius: 8px;
    box-shadow: var(--card-shadow);
}

/* 主要内容 */
main {
    max-width: 1200px;
    margin: 0 auto;
    padding: 2rem;
}

section {
    margin-bottom: 4rem;
}

h1, h2, h3 {
    color: var(--primary-color);
    margin-bottom: 1rem;
}

/* 项目卡片 */
.project-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 2rem;
}

.project-card {
    background: white;
    padding: 2rem;
    border-radius: 10px;
    box-shadow: var(--card-shadow);
    transition: transform 0.3s ease;
}

.project-card:hover {
    transform: translateY(-5px);
}

/* 活动列表 */
.activities-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 2rem;
    margin-top: 2rem;
}

.activity-card {
    background: white;
    padding: 2rem;
    border-radius: 10px;
    box-shadow: var(--card-shadow);
    transition: transform 0.3s ease;
}

.activity-card:hover {
    transform: translateY(-5px);
}

.activity-date {
    color: #666;
    font-size: 0.9rem;
    margin-bottom: 1rem;
}

/* 愿景部分 */
.vision-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 2rem;
}

.vision-item {
    background: white;
    padding: 2rem;
    border-radius: 10px;
    box-shadow: var(--card-shadow);
}

/* 引用样式 */
blockquote {
    border-left: 4px solid var(--primary-color);
    padding: 1rem 2rem;
    background: var(--secondary-color);
    margin: 2rem 0;
    font-style: italic;
}

/* 标语 */
.slogan {
    text-align: center;
    font-size: 1.5rem;
    color: var(--primary-color);
    margin-top: 2rem;
    font-weight: bold;
}

/* 页脚 */
footer {
    background-color: var(--secondary-color);
    padding: 2rem;
    text-align: center;
    margin-top: 4rem;
}

.footer-content {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 0.5rem;
}

.footer-content p,
.footer-content a {
    margin: 0;
    color: #666;
    text-decoration: none;
}

.footer-content a:hover {
    color: var(--primary-color);
    text-decoration: underline;
}

/* 响应式设计 */
@media (max-width: 768px) {
    .nav-links {
        flex-direction: column;
        align-items: center;
        gap: 1rem;
    }

    .project-grid,
    .vision-grid {
        grid-template-columns: 1fr;
    }

    main {
        padding: 1rem;
    }

    .activities-grid {
        grid-template-columns: 1fr;
    }
}

@media (min-width: 769px) and (max-width: 1024px) {
    .project-grid {
        grid-template-columns: repeat(2, 1fr);
    }
}
